Rear hub motor disc brake dilemma

P

praskal

1 W
Joined
Dec 25, 2007
Messages
60
Location
Corvallis, Oregon
So I finally got a full suspension MTB off craigslist (like this: http://www.velosklad.ru/i/models/sredn/132.jpg). The only problem is that it has dual disc brakes. I have a rear wheel X5 Phoenix hub motor. Because of this, I can't use the rear disk brake. And apparently I can't install V-brakes because you can't drill into aluminum (or whatever it is). I can't figure out how to put the disc on the left side of the X5 motor.

What suggestions do you guys have?? Should I just bag it and get a non-disc brake bike? Should I keep this bike and only use the front disc for braking??
 
I _think_ you can get a sideplate with disc bolt holes on it, but there's usually issues with caliper clearance between the hub and the motor. I hear Gustavs are pretty thin (plus they're good brakes to begin with), but they're expensive.

Other option is to try electronic braking via either regen or a plug brake.
 
One option would be to use the motor for a brake. There are a few threads on this. Basically a switch and some wire used as a resistor.

Check out Steveo's setup on page 4 http://endless-sphere.com/forums/vi...&st=0&sk=t&sd=a&hilit=resistor+brake&start=45

Another possible option would be to get a threaded side cover for the motor and use a threaded adapter to mount a disc on the brake side. There may not be enough clearance for the caliper in many cases.
 
It seems that using the motor for electronic braking would use alot of Current and possibly harm the electromagetic settup in the motor?
 
By the way, thanks for that link. There are some truly brilliant people on this forum.
 
praskal said:
So I finally got a full suspension MTB off craigslist (like this: http://www.velosklad.ru/i/models/sredn/132.jpg). The only problem is that it has dual disc brakes. I have a rear wheel X5 Phoenix hub motor. Because of this, I can't use the rear disk brake. And apparently I can't install V-brakes because you can't drill into aluminum (or whatever it is). I can't figure out how to put the disc on the left side of the X5 motor.

What suggestions do you guys have?? Should I just bag it and get a non-disc brake bike? Should I keep this bike and only use the front disc for braking??
Click to expand...


I have a full suspension like yours. I run Ubrakes. You can drill the aluminum and install a UBrake in the rear. That is a 20 minute job and around $30 in parts. I attached a picture.


You can also do custom work to install a disk. Doc has done it. The DC1 downhill build has one. Here is another:
http://e-mtb.com.au/images/DSC01070M.jpg

I actually found your thread looking for ideas on how to do it the *easy* way.

Of course, you can also run a motor brake or regen. I run regen on my setup as well so I actually have 3 brakes.
Regen or motor braking will heat your motor and decrease performance with heavy use. If you have a "normal" power setup it probably wont matter. With mine the motor gets INSANE hot when I use the regen too much.

-methods

EDIT: The key to the rear U Brake is an adapter plate.
http://www.jensonusa.com/store/product/ZZ307A14-Tektro+U1+Bmx+U+Brake+Adapter+Plate+Blk.aspx
Now you only need to drill one hole on top to center it. Zip tie the sides
 
methods said:
I have a full suspension like yours. I run Ubrakes. You can drill the aluminum and install a UBrake in the rear. That is a 20 minute job and around $30 in parts. I attached a picture.


You can also do custom work to install a disk. Doc has done it. The DC1 downhill build has one. Here is another:
http://e-mtb.com.au/images/DSC01070M.jpg
Click to expand...

That's a bitchin' lookin' bike - I would ride that! But I can't tell just how the disk was attached to the side plate. Any links to pictures or articles on how it's been done would be very helpful

methods said:
I actually found your thread looking for ideas on how to do it the *easy* way.
Click to expand...

I read l that like you think that's a BAD thing! I'd bet I'm not the only one here who seriously wants a fairly easy and not terribly expensive way to accomplish the task at hand. Maybe Santa Claus will bring me a machine shop! Props to anyone who really wants to do it the HARD way! :lol:

methods said:
Of course, you can also run a motor brake or regen. I run regen on my setup as well so I actually have 3 brakes.
Regen or motor braking will heat your motor and decrease performance with heavy use. If you have a "normal" power setup it probably wont matter. With mine the motor gets INSANE hot when I use the regen too much.
Click to expand...

But probably fine for a street bike, with the potential problem of cooking the controller or BMS, if I've understood other threads correctly. I'm thinking a big diode inline would lessen or eliminate that problem. My only experience with regen braking has been on an EGO scooter, and once I got used to it, I liked it pretty well.

methods said:
The key to the rear U Brake is an adapter plate.
http://www.jensonusa.com/store/product/ZZ307A14-Tektro+U1+Bmx+U+Brake+Adapter+Plate+Blk.aspx
Now you only need to drill one hole on top to center it. Zip tie the sides
Click to expand...

That's surely not a bad idea, but I really want a rear DISK brake!

ATB

BC
 
64ragtop said:
methods said:
I actually found your thread looking for ideas on how to do it the *easy* way.
Click to expand...

I read l that like you think that's a BAD thing! I'd bet I'm not the only one here who seriously wants a fairly easy and not terribly expensive way to accomplish the task at hand. Maybe Santa Claus will bring me a machine shop! Props to anyone who really wants to do it the HARD way! :lol:
Click to expand...



No way, I am with you man! I am trying to figure out how to put a disk on the back without having to go through hell to do it. Search on Doc. he has some close up pictures. If you figure it out, let us know :wink:

By the "easy way" I mean that I am looking for the slam dunk, bolt on, problem solved solution that somebody cooked up. Like maybe someone is making adaptor kits or something. I suck at machining. I can weld. . . but. . . It looks like vomit when I am done.

-methods
 
methods said:
No way, I am with you man! I am trying to figure out how to put a disk on the back without having to go through hell to do it. Search on Doc. he has some close up pictures. If you figure it out, let us know :wink:

By the "easy way" I mean that I am looking for the slam dunk, bolt on, problem solved solution that somebody cooked up. Like maybe someone is making adaptor kits or something. I suck at machining. I can weld. . . but. . . It looks like vomit when I am done.

-methods
Click to expand...

Cool :D My current project is that Giant Stiletto gathering dust in my living room. I got a local welding shop to do the set-up and neatly weld the lugs onto my front downtubes to add a u-brake setup. The rear of the bike has a disk brake bracket and I'm baffled at how to put a disk on the left side of my Xtalyte 5304. Gotta either get the spacing right on the disk mount on the motor sideplate or blow out the stock bracket and redo it and repaint the back end of the bike. But it's such a pretty candy apple red! :cry:

ATB

BC :mrgreen:
 
Only thing I am worried about is mounting the rotor. Spacing is easy to fix with an adapter bracket. You will need an adapter anyway to run a larger disk. . .

I just upgraded my front rotor to 8".
Sadly I was actually a little disappointed with the performance. No real noticeable change.
Unfortunately I was spoiled at the local bike shop. I rode some $4,500 downhill bike with a caliper that had like 4 pistons the size of my leg and it would lock up the front tire violently.

Thats what I need :mrgreen:

Anyway, if it makes you feel any better my first setup (which would go 45mph, 100V 5305) had ONLY a busted drum front brake, no rear brake, and no ebrake. It would take me like 300' to stop. I wore all the way through a pair of shoes. :mrgreen:

-methods
 
methods said:
Anyway, if it makes you feel any better my first setup (which would go 45mph, 100V 5305) had ONLY a busted drum front brake, no rear brake, and no ebrake. It would take me like 300' to stop. I wore all the way through a pair of shoes. :mrgreen: -methods
Click to expand...

Can't really say it makes me feel any better, but I'll tell ya this. I bought a 36 volt electric scooter (Freedom 959) that only has a band-type rear brake. The seller said the brake was shot, but I thought I fixed it by tweeking the screws on the housing 'til the brake lever would stop the wheel when I spun it by hand. So, I go out for the shakedown cruise that turned into a shakeUP cruise. Powering gently down a hill toward a railroad crossing, the arms drop, lights start flashing, and the bells are ringing. And NO BRAKES!!! :shock: Those shoes got a really good workout, and I was within a gnat's a** of letting the train HAVE the scooter. I ordered a new brake assembly the next day! And now I'm looking for a front fork assembly that I can add a disk to. Going is great, but stopping can be even BETTER!!!

ATB

BC
 
methods said:
I just upgraded my front rotor to 8".
Sadly I was actually a little disappointed with the performance. No real noticeable change.
Unfortunately I was spoiled at the local bike shop. I rode some $4,500 downhill bike with a caliper that had like 4 pistons the size of my leg and it would lock up the front tire violently.
Click to expand...

Methods, IIRC your bike has Juicy 5 brakes. They have the power of the Juicy 7 brakes but just with less adjustability. If you're not impressed with the braking power w/ 8" rotors then you need to either: check your pads, check the disc surface, bleed the brake lines, or adjust the lever reach (the set screw that sits under the lever). Juicy 5 and 7 brakes are considered some of the best out there for high performance, good modulation, low weight, and minimal fade from extended continuous braking.

On MTB's the 4 and 6 piston calipers are largely gimmicks. Good twin piston systems can lock the bike up on a dime with ease, and provide precise and powerful braking all the way to the edge of lock up.

Even with high end bikes, there's a huge difference between a properly set up and maintained one and one that isn't.
 
64ragtop said:
methods said:
You can also do custom work to install a disk. Doc has done it. The DC1 downhill build has one. Here is another:
http://e-mtb.com.au/images/DSC01070M.jpg
Click to expand...

That's a bitchin' lookin' bike - I would ride that! But I can't tell just how the disk was attached to the side plate. Any links to pictures or articles on how it's been done would be very helpful
Click to expand...

My understanding is that the e-mtb.com.au bike shown above is using a right hand side screw-on side cover on both sides. With a screw-on side cover on the left side of the motor, a screw on disc brake can be used or a screw on to 6 ISO hole pattern adaptor can be used. ebike.ca had these on their online store at some point.

The ebike.ca site says on the crystalyte hubmotor page that there is some issue with bearing sizes with the X5 right screw on side cover on the left side, but e-mtb.com.au has obviously overcome this issue somehow.

Cheers!
 
voicecoils said:
My understanding is that the e-mtb.com.au bike shown above is using a right hand side screw-on side cover on both sides. With a screw-on side cover on the left side of the motor, a screw on disc brake can be used or a screw on to 6 ISO hole pattern adaptor can be used. ebike.ca had these on their online store at some point.

The ebike.ca site says on the crystalyte hubmotor page that there is some issue with bearing sizes with the X5 right screw on side cover on the left side, but e-mtb.com.au has obviously overcome this issue somehow.

Cheers!
Click to expand...

That's what I remember being told by my Canadian friends on the phone, but somehow I didn't quite get it. I've sent a note to e-mtb.com.au. maybe there is hope yet! Or maybe Santa Claus will bring me a machine shop!

ATB

BC
 
voicecoils said:
methods said:
I just upgraded my front rotor to 8".
Sadly I was actually a little disappointed with the performance. No real noticeable change.
Unfortunately I was spoiled at the local bike shop. I rode some $4,500 downhill bike with a caliper that had like 4 pistons the size of my leg and it would lock up the front tire violently.
Click to expand...

Methods, IIRC your bike has Juicy 5 brakes. They have the power of the Juicy 7 brakes but just with less adjustability. If you're not impressed with the braking power w/ 8" rotors then you need to either: check your pads, check the disc surface, bleed the brake lines, or adjust the lever reach (the set screw that sits under the lever). Juicy 5 and 7 brakes are considered some of the best out there for high performance, good modulation, low weight, and minimal fade from extended continuous braking.

On MTB's the 4 and 6 piston calipers are largely gimmicks. Good twin piston systems can lock the bike up on a dime with ease, and provide precise and powerful braking all the way to the edge of lock up.

Even with high end bikes, there's a huge difference between a properly set up and maintained one and one that isn't.
Click to expand...


Actually I have the Juicy 3 single piston. I am quite sure that they are weak.
Nothing like the brakes I tried at the store.

-methods
 
Got the response from the Aussies:

G'day Bob,

Anything is possible

The Giant Stilleto is something that we're close to getting into ourselves very soon.

For your disc brake the answer is very simple. You need a disc brake compatible cover on the left side.

We sell them for $60 AUD and a further $30 AUD for the compatible disc....... so about 2 bucks... USD (kidding) . Shipping will be around $30AUD.

You need to use the Crystalyte specific disc so that you can fit it to the motor. A standard disc just doesn't fit. You have a choice of 6", 7" or 8" rotors.

Just to make 100% sure of what you need.... if you can send us some pics of the rear end of the bike from a few different angles, we'll have a quick look to make sure that you're not wasting your money.

Looking forward to hearing back from you,

John Karambalis
B.Eng (Mech)
A.Dip Eng (Aero)

E-MTB
http://www.emtb.com.au
Click to expand...

Gotta love that "CAN DO!" spirit! :) And 300.00 Australian Dollars = 200.84 USD. Gotta take some pictures!

Oh, and check their website! one "package" they offer is: the E-liminator Stage 3 LiPo - $5650 AUD (= $3,781.18 USD!

ATB

BC
 
64ragtop said:
Gotta love that "CAN DO!" spirit! :) And 300.00 Australian Dollars = 200.84 USD. Gotta take some pictures!

ATB

BC
Click to expand...

Cool.

Re the Stilleto: http://www.youtube.com/watch?v=5DNYZQMk4UA

Where do you get $300 from?
I get $60 +$30 + $30 = 120 Australian dollars = 80.79600 U.S. dollars

I've just put my order in for the same for my 5304. Side cover and an 8" disc :p
 
Wow. . . Grand slam?

Nice!

Now. . . I have another thread going around here somewhere where somebody explained how to re-shim the motor so that it does not wobble. When I find the link I will post it. Point being, many X5's wobble so you may want to clean that up first.

If I recall, Doc claimed to have cut his on a lathe with the X5. . . Forcing the surface to be true to the axle.

So how did you find this guy again? Is there a thread I am missing and how come the ebikes.ca site says that it can only be done with the smaller motors?

Thanks for posting the info!!!

-Patrick

EDIT: DUDE, THOSE GUYS ROCK! Go check them out!
http://www.emtb.com.au/

I am excited again! I have been wanting to switch over to double wide wheels but I thought I was stuck with the U Brake. Now that I know I have another solution, I am going to go start shopping right now! That bike they built is bad-ass^2 !!!
 
methods said:
So how did you find this guy again? Is there a thread I am missing and how come the ebikes.ca site says that it can only be done with the smaller motors?
Click to expand...

I read the ebike.ca site too. It's a discrepancy that I haven't seen resolved yet.

However, e-mtb.com.au is clearly doing it as the picture shows. There are a number of examples on their site.
DSCF6714R.JPG


Cheers!
 
cant wait
cant wait
cant wait
cant wait
cant wait!!!

I am going to go get some double wides right now!
That is exactly what I was looking for.
Even if the alignment is not perfect, I can build a little adapter plate.

oh boy
oh boy
oh boy.....

Project Mayhem!


-methods
 
Thanks for the math check, voicecoils, I dunno where the 300 came from either, but I like the new number even better!
Mighty glad I've not been braggin' about my math skills :oops: :oops: :oops:

ATB

BC
 
EDIT: Order on hold. I think these are set up for the 12mm axle. They may be able to machine them out to the right size. Will notify when I find out.

Ok, I ordered two of the adapters and two disks.
Lead time is long but thats fine. It will give me something to look forward to.

In the mean while I can spend a little more time working on Project Mayhem to make it "jump worthy". After watching those videos I am convinced that I need to catch more air!


Ok, now on my list to buy:

Front and rear Double wide rims
Front and rear 3"+ tires
Rear avid 8" adapter & cps
Used front Avid Juicy 5 for front

Gangsta!


If anyone wants to get in on my buy (to possibly save on shipping) you have another few hours. Mind you I cant vouch for these guys or this product. I can say that they are very good communicators, they build bad ass bikes, and I am confident that they will "do right". I will be shipping to the Bay Area of California.

-methods
 
hmmmm.....

Does anyone know what size bearing is in the "common" X5?
This quote from ebikes.ca claims they are different:

"Rear 500 series: The Crystalyte rear disk 5300 series hub motors were defective by design in that they only used a 12mm axle which was prone to spinout with the high torque of this hub, and therefore we have stopped carrying them. It is not possible to use one of the spare threaded 500 series side covers on the left and use a screw-on disk adapter, because the ball bearing size on these threaded side covers is smaller than that on the non-threaded units, and won't fit on the axle. The best approach in this case is to get the regular rear 5300 series and then drill and tap the side cover so that the disk adapter can be bolted on. Note that there is some complication feeding the wires out of the disk setups, and that a custom 'U' shaped spacer washer may be required."

E-MTB states that the bearing is a 6004

Can anyone confirm or deny that?
I dont particularly want to take my motor apart when I know you characters probably know off hand.

and btw:
How come other people are not buying these from Crystalyte? What gives?

-methods
 
I don't know. What you read on ebike.ca is what I've read too and what I've seen on e-mtb.com.au is what you've seen :D

Perhaps you can get e-mtb.com.au to explain more thoroughly or ask ebike.ca why they've said that when the screw on covers are clearly being used on both sides...

My cover is ordered and I trust e-mtb.com.au so I'm sure they'll be a way to get it to work :p
 
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